1. Field of the Invention
The invention relates to an apparatus for use in creating butt-weld joints for tubes arranged in a restricted-radial-clearance arrangement.
2. Description of the Related Art
Boiler tubes may be subjected to high temperature and may experience relatively high stress and strain, which may lead to wear. Accordingly, at times, it is necessary to replace the tubes, or portions of the tubes within a boiler. Such replacement includes identifying a tube, or portion of a tube, to be replaced, removing a damaged portion of the tube, and butt-welding a new portion to a lower portion of the original tube.
Boiler tubes, however, are often tightly bundled having narrow radial gaps between adjacent tubes, which makes butt-welding difficult. For example, the tubes may be arranged with a minimum radial clearance between latitudinally adjacent tubes ranging from about 0.5 inches, or less, to about 3 inches, alternatively from about 1.5 inches to about 3 inches. The tubes may also be arranged with a minimum radial clearance between longitudinally adjacent tubes ranging from about 2 inches, or less, to about 4 inches.